PSI - Issue 28

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Author name / Structural Integrity Procedia 00 (2019) 000–000

Rhys Jones et al. / Procedia Structural Integrity 28 (2020) 26–38 Appendix B. Determining the values of A and ∆� As explained in Yao et al. (2018), and in the present paper, the values of A and ∆� ��� are chosen so as to ensure that Equation (2) best fits an experimental set of test data of log da/dN versus log ∆√ over the entire range of FCG rates. In the seventy-seven tests analysed in the present paper, the values of A and ∆� ��� were chosen so that, for a given set of test data, the log da/dN versus log � ∆√�� ∆�� ��� √��� �� ��� /√�� � plots became virtually linear. After the individual linear relationship for a given set of test data points had been determined, a combined plot of each of the different seventy-seven tests was assembled, as shown in Fig. 3. Here it can be seen that, allowing for experimental error, the resultant seventy-seven plots enable a single, linear, ‘master’ relationship to be defined. This unique, linear, ‘master’ relationship that may be readily fitted to all the seventy-seven sets of data is shown in Fig. 3 and gives a value of the linear coefficient of determination, R 2 , of 0.994. Values of the slope, n , and intercept, D , of this ‘master’ relationship are given in Fig. 3, and are subsequently also used to predict the ‘upper-bound’ FCG rate curve, as described above. References ASTM, 2014. Measurement of FCG Rates . ASTM E647-13. West Conshocken, USA. Brunner AJ., Pinter G., Murphy N., 2009. Development of a Standardized Procedure for the Characterization of Interlaminar Crack Growth in Advanced Composites under Fatigue Mode I Loading Conditions. Engineering Fracture Mechanics 76, 2678-2689. Composite Materials Handbook-17-3G, 2012. Volume 3, Chapter 4. Polymer Matrix Composites Materials Useage, Design and Analysis . SAE International, Warrendale, USA. Federal Aviation Authority (FAA), 2009. Airworthiness Advisory Circular No: 20-107B. Composite Aircraft Structure, 09/08/2009. Hartman, A., Schijve J., 1970. The Effects of Environment and Load Frequency on the Crack Propagation Law for Macro FCG in Aluminium Alloys. Engineering Fracture Mechanics 1, 615-631. Jones R., Hu W. and Kinloch AJ., 2015. A Convenient Way to Represent FCG in Structural Adhesives. Fatigue and Fracture of Engineering Materials and Structures 38, 379-391. Jones R., Kinloch AJ., Hu W., 2016. Cyclic-FCG in Composite and Adhesively-Bonded Structures: The FAA Slow Crack Growth Approach to Certification and the Problem of Similitude. International Journal of Fatigue 88, 10-18. Jones R., Kinloch AJ., Michopoulos JG., Brunner AJ., Phan N., 2017. Delamination Growth in Polymer-Matrix Fibre Composites and the Use of Fracture Mechanics Data for Material Characterisation and Life Prediction. Composite Structures 180, 316-333. Jones, R., Peng, D., Michopoulos, J., Kinloch, AJ., 2020. Requirements and Variability Affecting the Durability of Bonded Joints. Materials 13, 1468. Murri GB., 2014. Effect of Data Reduction and Fiber-Bridging on Mode I Delamination Characterization of Unidirectional Composites. Journal of Composite Materials 48, 2413-2424. Niu, MCY., 1992. Composite Airframe Structures: Practical Design Information and Data , Conmilit Press, Hong Kong. Paris PC., Gomez RE., Anderson WE., 1961. A Rational Analytic Theory of Fatigue. The Trend in Engineering 13/1, 9-14. Paris PC., Erdogan F., 1963. Critical Analysis of Crack Growth Propagation Laws. ASME Transactions, Journal of Basic Engineering 85D, 528-534. Paris PC., 2014. A Brief History of the Crack Tip Stress Intensity Factor and its Application. Meccanica 49, 759-764. Pascoe JA., Alderliesten RC., Benedictus R., 2013. Methods for the Prediction of Fatigue Delamination Growth in Composites and Adhesive Bonds - A Critical Review. Engineering Fracture Mechanics 112-113, 72-96. Rans C., Alderliesten R., Benedictus R., 2011. Misinterpreting the Results: How Similitude can Improve our Understanding of Fatigue Delamination Growth. Composites Science and Technology 71, 230–238. Rouchon J., 2009. Fatigue and Damage Tolerance Evaluation of Structures: The Composite Materials Response . 22nd Plantema Memorial Lecture, 25th ICAF Symposium, Hamburg, Germany, Rotterdam, The Netherlands, National Aerospace Laboratory NLR, NLR-TP-2009 221. Sih, GC., Paris PC., Irwin GR., 1965. On Cracks in Rectilinearly Anisotropic Bodies. International Journal of Fracture Mechanics 1, 189-203. 37